Hold gizmo axis transformation shortcut
You can easily rotate the view by pressing the middle mouse button and moving the mouse. To pan the view, do the same but also maintain Shift. To zoom in/out, do the same but also maintain Ctrl (or simply use the mouse wheel).

You can use the numpad keys to set the view to : 


front 1, back Ctrl+1
right 3, left Ctrl+3
top 7, bottom Ctrl+7
camera 0